Cable ties have long been used to bundle one or more articles such as cables and the like. These ties are typically plastic elongate straps having a tail at one end and a locking head at the other end for receiving the tail. The head includes a locking mechanism in the form of an integrally formed locking pawl (one-piece) or an inserted metallic barb (two-piece).
Both the one-piece and two-piece cable ties operate substantially the same way in that the free end of the tail is looped around the bundle and pushed or pulled through the head so as to engage the pawl or barb therein. The cable tie is then tensioned around the bundle as desired. The pawl or barb engages the tail as it passes through the head and prevents the tail from backing out even under a load. The excess tail then extends outside the head.
While many patents have been issued directed to the shape or construction of the cable tie, its barb or pawl, and/or its head, few address the removal of the excess tail from the cable tie once the tie has been installed. Instead, the user is left to his/her own devices such as employing a tool to cut the excess length off.
U.S. Pat. No. 3,739,430 is an early attempt at providing some mechanism of removing the excess tail length from the tie after tensioning. In accordance with this patent a series of slits are cut into the opposite shorter sides of the strap at spaced intervals. After the tail is pushed through the head, the tail is twisted about its longitudinal axis as shown in FIGS. 4 and 9 until the tail separates from the tie. While this method enables a user to detach a two-piece cable tie tail without using tools, this method is not suitable for one-piece cable ties. This is because these side slits will significantly reduce the cross-sectional area of the one-piece tie and hence such a side-slitted cable tie cannot attain the same rating as its un-slitted twin.
While this side-slitting method is suitable for two-piece cable ties, such technology is not readily transferable to one piece cable ties. This is because two-piece cable ties generally have a smooth planar tail with no interruptions, ridges or teeth therein since it is intended for the metal barb to bite into the tail at any location along its length. In other words, its cross-sectional area is constant along the length of the tail. In contrast, the tail of one-piece cable ties are specially designed with at least one surface (and maybe its opposite surface too) configured with a series of ridges or teeth therein that are intended to be engaged (not embedded) by the pawl. Hence, the cross-sectional area of the tail of a one-piece cable tie varies depending on whether the view is through a tooth or the space between adjacent teeth. Thus, the placement of side slits as shown in the '430 patent will compromise the strength of a one-piece cable tie if the slits align with the recess between the teeth. This is because the slit would further erode the load-bearing cross-sectional area of the tie thereby rendering it only marginally useful.